Q&A: What is the difference between laser thermokeratoplasty and microwave thermokeratoplasty?

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What is the difference between laser thermokeratoplasty and microwave thermokeratoplasty? Which one is more effective in the treatment of keratoconus? Is LTK dangerous since keratoconus makes the cornea paper thin? Side note: I've already had cross-linking done

- Wyatt


Emil William Chynn, MD, FACS, MBA - LocateADoc.com

I'm sorry, but in 2014 you really should not be even considering any kind of thermoplasty for KC. That was a shrinking device that isn't very reliable or predictable, that we sometime used for KC, when we didn't have better options. The analogy would be putting a sweater that was too large into the dryer, and hoping it shrinks to a better size. While you know it will shrink, it's impossible to predict or control in a precise manner how much it will shrink--that's the basic problem with thermoplasty.
The treatment for KC now in 2014 is CXL, or corneal cross-linking, which has been approved in Europe for over a decade. The FDA is being strangely slow in approving CXL in this country. I went to Columbia Medical School and graduated in 1992, so was involved in recruiting patients for CXL trials for the FDA at Columbia way back in 2009. That study closed a long time ago, and had positive results, but the FDA keeps asking for more and more data--meanwhile, European patients have been treated safely and effectively with CXL for over a decade.
Therefore, Park Avenue LASEK decided to offer CXL to our patients in 2011, becoming the 3rd medical center in NYC to offer CXL (the vast majority of large hospitals in NYC do not even own a CXL machine). We clearly inform the patients that CXL is not yet FDA-approved, but I can legally and ethically perform this procedure, as long as he feels it is to the benefit of the patient, and consents the patients appropriately. Approximately 300 eye surgeons in the US are now performing CXL, so it is not really what you would call "experimental" (especially since over 100,000 procedures have now been performed around the world), it is what you would call "state-of-the-art."
If you've already had CXL performed, there shouldn't be any need for thermoplasty, unless you have significant irregular astigmatism. There are several alternatives you can do for that besides thermoplasty, including Intacs, just using a RGP, and LASEK. If you were in NYC, I would invite you to come in for an evaluation at my center, to see which of these options would be best for you. If you are not in NYC, you can just go to the ASCRS website, and find someone who completed a Fellowship in Cornea, and performs CXL plus LASEK or Intacs or thermoplasty, to get a good opinion.
Hope this helps, and feel free to call my office and speak to me if you need more guidance.

--Emil William Chynn, MD, FACS, MBA
New York, NY


Emilio M. Justo, M.D. - LocateADoc.com

Dear Wyatt...........thank you for your excellent question. However, this type of question is a very advanced, detailed question that is best served by a corneal sub-specialist who treats keratoconus patients (which I do not). Therefore, I will defer to the expert opinions of others.
Good luck!

--Emilio M. Justo, M.D.
Sun City West, AZ

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